Publish web app shows differences with identical files

Hi

I've started using "Publish Web App" recently (VS 2015, Web Deploy 3.6) and the issue I have is that when click "Start Preview" it shows files that are identical. 

I've tried:

1) Copy from local to serve

2) copy from server to local

3) Make a difference in the file and copy

4) Use <MSDeployUseChecksum>true</MSDeployUseChecksum>

5) I've set server timezone to the same as local.

and I still get "update" action. When I click the file and preview it shows no changes.

Any suggestions how I can troubleshoot or fix this?

Many thanks in advance!

Emil